This invention relates to improvements in high smoothness grinding process and apparatus for metal materials, and more particularly to the high smoothness grinding process and apparatus for making a surface of the metal material highly smooth by using a super abrasive grain grinding wheel.
In order to obtain a highly smooth surface of a metal material by machining, hitherto a grinding step and a lapping (super-finishing) step are carried out as a grinding process for the metal material, or otherwise a rough grinding and a finish grinding step (plural steps of grindings) are carried out as a grinding process for the metal material.
In such grinding processes, it is required to transfer the metal material or workpiece from one grinding device to another grinding device every time a step is changed into another step. This prolongs a machining time for the workpiece and increases the number of steps and machining devices, thereby raising a machining cost. As a result, it is desired and proposed to obtain a highly smooth surface at only a single step by employing a plunge grinding, as disclosed in Japanese Patent Provisional Publication No. 2003-94296.